Many medical disorders, including neuropsychiatric disorders, cardiac related disorders and fatigue are traditionally treated with pharmacotherapy and/or psychotherapy. However, a substantial percentage of patients with these and other conditions do not recover despite multiple trials of treatment and there may be significant and long term side effects to the traditional treatment methods.
For example, interventions for fatigue commonly employ medications, particularly psychostimulant medications. Such medications include methylphenidate, amantadine, pemoline, and modafinil (reviewed by Peuckmann et al., Cochrane Database Syst Rev 2010, 11:CD006788). These medications carry potential for side effects, such as blurred vision, depression or anxiety, liver failure, psychosis, suicidal thinking, swelling of the hands/leg/feet, shortness of breath, palpitations, elevated blood pressure, anorexia and addiction.
For some medical disorders, brain stimulation has been a primary treatment alternative, and electroconvulsive therapy (ECT, or “electroshock” therapy) has been the dominant brain stimulation approach since the first part of the 20th century. ECT carries risks of memory and other cognitive side effects, considerable cost, and risks of anesthesia. Two implantable approaches have also been described: deep brain stimulation (DBS), in which electrodes are implanted directly within the brain, and vagus nerve stimulation (VNS) in which stimulating electrodes are implanted on the vagus nerve in the neck. While the U.S. Food and Drug Administration (FDA) have approved systems for deep brain stimulation for the treatment of essential tremor, Parkinson's disease, dystonia and obsessive compulsive disorder, DBS is presently an experimental intervention for other neuropsychiatric conditions. The risks of DBS include infection, hemorrhage, and injury to deep brain structures. In reports of clinical studies with VNS, many of the patients who undergo VNS treatments do not achieve remission, and there is no reliable predictor of good outcomes from the implanted VNS device.
Against this backdrop, the present disclosure is provided.
The information included in this Background section of the specification, including any references cited herein and any description or discussion thereof, is included for technical reference purposes only and is not to be regarded as subject matter by which the scope of the invention is to be bound.